KR100938435B1 - Production method of cos and apparatus thereof - Google Patents

Abstract

PURPOSE: A synthesis method of carbonyl sulfide and a synthesis apparatus thereof are provided to synthesize carbonyl sulfide economically with only simple reaction equipment, to minimize the generation of by-products, and to ensure continuous mass production. CONSTITUTION: A synthesis method of carbonyl sulfide using carbon monoxide gas and liquid sulfur as a raw material comprises a step for reacting carbon monoxide gas and liquid sulfur through by bubbling and supplying carbon monoxide gas to a reactor(21) in which liquid sulfur is contained thereinside and the temperature and pressure control is enabled through a gas-solid contact method.

Description

Synthesis method and synthesis reaction apparatus of carbonyl sulfide

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for synthesizing and reacting carbonyl sulfide (COS), which is used as a main raw material for pesticides, medicines, and various chemical products, and has recently attracted attention as a novel etching gas material in semiconductor manufacturing processes.

More specifically, carbonyl sulfide which can minimize the formation of high yields and side reactions in the gas-liquid contact method by supplying and bubbling carbon monoxide (CO) through a deep nozzle submerged in a reactor containing liquid sulfur to a certain depth. COS) and a synthesis method and a synthesis reactor.

In general, carbonyl sulfide (COS) is widely used as a major raw material for agrochemicals, medicines and various chemicals due to its unique molecular structure with two double bonds.

In recent years, when the etching process, which is the most important process of semiconductor manufacturing, is used together with the existing etching gas, the results of the etching properties can be greatly improved. It is a substance.

Such carbonyl sulfide (COS) is usually produced using carbon monoxide and sulfur as raw materials.

Many methods have been proposed for synthesizing carbonyl sulfide from carbon monoxide and sulfur as raw materials.

For example, methods for producing carbonyl sulfide in high yields by gas phase reaction of carbon monoxide and sulfur using sulfur-containing metal compounds such as zinc sulfide, cadmium sulfide, and lead sulfide as catalysts are known.

However, when carbonyl sulfide is synthesized in this way, although the yield of carbonyl sulfide can be increased to 90% or more, byproducts due to impurities contained in the catalyst as well as periodically regenerating or replacing the catalyst are required. The disadvantage is the inevitable generation of unwanted byproducts such as hydrogen sulfide.

As another method, as disclosed in US Pat. No. 4,078,045, the sulfur supplied as shown in FIG. 1 is heated to make a gas, the gaseous sulfur and carbon monoxide are mixed to make a mixed gas, and the mixed gas is reactor. It is a method for synthesizing carbonyl sulfide by supplying to.

In Fig. 1, 1 is a gas phase reactor, 2 is a carbon monoxide supply pipe, 3 is a mixed mixer, 4 is a sulfur supply pump, 5 is a sulfur supply pipe, 7 is a heater for heating sulfur, and 6, 8, 9 are Connection tube, 10 is a carbonyl sulfide (COS) discharge tube.

In this method, a technique for synthesizing carbonyl sulfide in high yield without using a catalyst is proposed, but a raw material mixing device for heating sulfur to form a gas and mixing the sulfur gas and carbon monoxide, The reaction device for receiving and reacting the mixed gas mixed with sulfur and carbon monoxide is separate and expensive for the equipment, and high energy is required to maintain each temperature, which is not economically desirable. Manufacturing costs will rise.

In addition, when carbon monoxide is mixed with gaseous sulfur to make a mixed gas, in order to obtain high yield of carbonyl sulfide, it is necessary to maintain a constant ratio of carbon monoxide and sulfur, and evaporate sulfur to mix with carbon monoxide at a constant ratio. Practically poses significant difficulties.

The present invention is to solve the problems of the prior art in synthesizing carbonyl sulfide with carbon monoxide and sulfur as a raw material and to provide a method for synthesizing carbonyl sulfide economically and technically convenient.

The first object of the present invention is to economically and efficiently carbonyl sulfide by solving the problem of maintenance and maintenance due to the regeneration and replacement of the catalyst in the process of synthesizing carbonyl sulfide using a catalyst, generation of by-products by impurities, etc. It is to provide a method for synthesizing.

Another object of the present invention is to synthesize carbonyl sulfide in a simple manner by solving problems such as duplication of a device and difficulty in managing process conditions in synthesizing carbonyl sulfide using carbon monoxide and sulfur as raw materials. To provide a way.

It is still another object of the present invention to provide a reaction apparatus capable of synthesizing high yield carbonyl sulfide by reacting gaseous carbon monoxide with liquid sulfur in an economical and simple manner so as to achieve the above object.

Synthesis method of carbonyl sulfide of the present invention to achieve this object, the synthesis of carbonyl sulfide to supply carbon monoxide to the liquid sulfur stored inside the reactor capable of pressure and temperature control to react by gas-liquid contact method It is a way.

In this way, carbon monoxide was supplied to the liquid sulfur to synthesize carbonyl sulfide by the gas-liquid contact method, thereby preventing the maintenance and maintenance of the catalyst by the regeneration and replacement of the catalyst and the generation of by-products due to impurities.

Sulfur in the reactor is maintained at a temperature of 350 ~ 550 ℃ by heating means, the reactor internal pressure is maintained at 0 ~ 5kg / cm ² to react carbon monoxide with sulfur to synthesize carbonyl sulfide.

The carbon monoxide is supplied to the liquid sulfur, but the carbon monoxide is supplied into the liquid sulfur so that gas-liquid contact occurs. Preferably, the carbon monoxide gas is supplied at a depth of 5 cm or more at the interface (water surface) of the liquid sulfur.

The carbon monoxide gas is preferably supplied to bubbling in liquid sulfur.

In the reaction apparatus for synthesizing carbonyl sulfide, the reaction apparatus for synthesizing carbonyl sulfide (COS) by reacting carbon monoxide (CO) and sulfur (S) to achieve the synthesis method of carbonyl sulfide of the present invention, It has an internal space to store the liquid sulfur (S), and equipped with a heating means capable of temperature control, pressure control reactor, and carbon monoxide (CO) in the liquid sulfur (S) stored in the inner space of the reactor It is configured to include a carbon monoxide supply pipe installed to supply a carbon dioxide sulfide (COS) discharge pipe is installed on top of the reactor and reacted to synthesize the carbonyl sulfide (COS),

At the end of the carbon monoxide supply pipe (the end of the pipe submerged in the liquid), a bubbling device, such as a bubbler or sparger, may be installed to help disperse bubbles, or the pipe may be processed to facilitate bubble generation, or It can be used as it is. That is, if the carbon monoxide supplied to the reactor is made to be discharged in the liquid sulfur, there is no restriction in the supply pipe of carbon monoxide.

According to the method of the present invention, a carbonyl sulfide gas useful as a simple synthesis reactor can be continuously and efficiently synthesized economically and efficiently.

As described above, the method of synthesizing carbonyl sulfide according to the present invention can suppress production of by-products due to deterioration of catalyst activity or impurities contained in the catalyst by not using a catalyst, unlike the prior arts. Compared to the gas phase reaction in which gaseous carbon monoxide reacts with sulfur in the gas phase, the reaction can be carried out at a significantly lower temperature, thereby lowering the energy cost due to the high temperature, and preventing the decomposition of the reaction product to produce carbonyl sulfide with high yield at an economical rate. There is a characteristic.

In addition, the prior art requires a mixing device for mixing the two raw materials with the reactor to make a mixed gas of carbon monoxide and sulfur, the present invention does not require a separate mixing device, the reaction is only by supplying carbon monoxide in the reactor Because it is made, there is no need to operate to match the mixing ratio of the two raw materials, there is an advantage that the process is simple, but can be mass-produced in continuous operation.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms or words used in the specification and claims should not be construed as having a conventional or dictionary meaning, and the inventors should properly explain the concept of terms in order to best explain their own invention. Based on the principle that can be defined, it should be interpreted as meaning and concept corresponding to the technical idea of the present invention.

Therefore, the embodiments described in the specification and the drawings shown in the drawings are only the most preferred embodiment of the present invention and do not represent all of the technical idea of the present invention, various modifications that can be replaced at the time of the present application It should be understood that there may be equivalents and variations.

In the method for synthesizing carbonyl sulfide of the present invention, the carbon monoxide gas and the liquid sulfur are supplied to the sulfur liquid by bubbling carbon monoxide by supplying carbon monoxide through a carbon monoxide supply pipe installed to immerse in the sulfur liquid in a reactor containing liquid (liquid) sulfur. It is to provide a new method of synthesizing carbonyl sulfide that can be synthesized carbon-sulfur without gas-liquid contact without a separate mixing device or catalyst.

Applicants of the present invention, in order to develop a technology that can be more easily and economically produced carbonyl sulfide with a wide range of applications, as a result, gas-liquid contact reaction to the conventional gas phase reaction method or gas phase contact method using a catalyst Compared to the present invention, the present inventors have found that carbonyl sulfide can be easily synthesized in high yield while significantly reducing the production of impurities.

Such a method for synthesizing carbonyl sulfide of the present invention,

The sulfur in the liquid phase is supplied through the sulfur supply pipe 27 into the reactor 21 capable of controlling temperature and pressure to fill a predetermined amount.

Carbon monoxide (CO) is supplied through the supply pipe 23 in the reactor 21 in which the liquid sulfur is stored.

The carbon monoxide supplied through the supply pipe 23 is supplied into the liquid sulfur so that a gas-liquid contact reaction may occur.

The nozzle which is the end of the supply pipe 23 is to be immersed in a depth of at least 5 cm at the sulfur interface (water surface) of the liquid phase stored in the reactor 21.

This is for the carbon monoxide supplied to the supply pipe 23 is supplied at a depth of at least 5 cm at the sulfur interface (water surface) in the liquid phase so that the gas-liquid contact reaction occurs.

In the method for synthesizing carbonyl sulfide using carbon monoxide and liquid sulfur according to the present invention, the reaction conditions are as follows.

In the gas-liquid contact reaction of carbon monoxide and liquid sulfur, the reaction temperature is 350 to 550 캜. To this end, the liquid sulfur in the reactor 21 is maintained at 350 to 550 ° C. by the heating means 22.

In more detail, the gas-liquid contact reaction temperature is preferably 400 to 500 ° C, most preferably 430 to 480 ° C.

In the gas-liquid contact reaction of carbon monoxide and liquid sulfur, the reaction pressure is 0 (atmospheric pressure) to 5 kg / cm ² -G.

In more detail, the reaction pressure is preferably 0.5 to 3 kg / cm ² -G, more preferably 1 to 2.5 kg / cm ² -G.

The carbon monoxide is supplied by bubbling through the nozzle of the supply pipe immersed in the liquid sulfur under the reaction temperature and the reaction pressure conditions.

This makes it possible to continuously produce carbonyl sulfide in high yield without a catalyst or a separate high temperature gas phase reactor.

Reactors are more advantageous for vertical or column type reactors than horizontal type to increase gas-liquid contact efficiency, but any type of reactor can be used as long as gas-liquid contact is sufficient.

The reaction apparatus for synthesizing carbonyl sulfide of the present invention includes a reactor 21 having an inner space 21a formed in a vertical cylinder shape as shown in FIG. 2, a heating means 22 for heating the reactor 21, and the reactor. Carbon monoxide supply pipe (23) for supplying carbon monoxide in (21), sulfur supply pipe (27) for supplying sulfur in the reactor (21), and discharge pipe for discharging carbonyl sulfide synthesized by reacting in the reactor (21) It consists of 24.

The reactor 21 is provided with a water level meter (not shown) capable of measuring the level of liquid (liquid) sulfur, a temperature sensor 25 for measuring the internal temperature, and a pressure sensor 26 for measuring the internal pressure. .

The carbon monoxide supply pipe 23, the sulfur supply pipe 27 and the discharge pipe 24 for discharging carbonyl sulfide are provided with valves for controlling supply and discharge, respectively.

The heating means 22 usually uses an electric heater, and controls the reaction temperature.

The reaction pressure inside the reactor 21 is kept constant by adjusting the gas flow rate flowing out of the reactor 21 with a valve. That is, it adjusts using the valve provided in the discharge pipe 24 which discharges carbonyl sulfide.

Sulfur supplied into the reactor 21 may be in a solid state such as powder form, granule form or pellet form or any form such as liquid form, but a product having a purity of 99% or more in order to minimize generation of side reactions in the reaction. It is good to use

In the case of using solid sulfur as a raw material, it may be directly added to the reactor, then heated to melt to a liquid state, and then reacted by supplying carbon monoxide. It is preferable to supplement the reactor 21 batchwise.

In the case of making sulfur in a liquid state in a separate container and supplying it to the reactor 21, impurities such as moisture are removed in advance by melting sulfur in a solid state in a separate container and bubbling with an inert gas such as nitrogen. In the case of replenishing sulfur, sulfur can be replenished without exposing the reactor to the outside, thereby minimizing the inflow of impurities, thereby minimizing the generation of impurities in the reaction.

When supplying sulfur in a liquid state to the reactor, it can be fed to the reactor using a pump, or pressurized with an inert gas and then to the reactor using a pressure difference.

The liquid sulfur level in the reactor is preferably maintained so that the nozzle of the end formed in the carbon monoxide feed pipe is locked to a depth of at least 5 cm. This is to allow the carbon monoxide gas to be discharged at a depth of at least 5 cm at the interface (water surface) of the liquid sulfur.

The depth is determined in consideration of the gas-liquid contact time depending on the type of reactor or the flow rate of carbon monoxide gas discharged.

If the submerged depth of the carbon monoxide supply line is too low, sufficient contact between the gas of carbon monoxide and sulfur of the liquid 9) will not occur, and the amount of unreacted carbon monoxide will increase. This is not good because the yield can be lowered.

Normally, the end nozzle formed in the carbon monoxide supply pipe is positioned at a depth of 5 to 100 cm from the interface (water surface) of the liquid sulfur.

The temperature of the reactor means the reaction zone where the reaction takes place, that is, the temperature of the liquid sulfur part, and is preferably maintained at 350 to 550 ° C, preferably 400 to 500 ° C, and more preferably 430 to 480 ° C.

If the reaction temperature is too low, the reaction activity is lowered and the reaction yield is lowered. If the reaction temperature is too high, not only the amount of by-products is increased but also the amount of sulfur evaporation increases, so that the loss of sulfur and the evaporated sulfur condenses in the pipe and the pipe is closed. Results.

The reaction pressure is 0 (atmospheric pressure) - sikidoe maintained in the range of 5kg / cm ² -G, preferably from the reaction to be better than the 0.5 ~ 4kg / cm ² -G, is maintained at 1 ~ 3kg / cm ² -G It is advantageous.

When the reaction pressure is low, the evaporation amount of sulfur is relatively increased at the same temperature, so that the amount of loss is increased, the gas-liquid contact efficiency is lowered, and the yield is lowered.

If the reaction pressure is too high, the feed pressure of the raw material must also be increased, which increases the risk and may result in decomposition of carbonyl sulfide or increased by-products such as carbon disulfide (CS ₂ ).

Carbon monoxide is continuously introduced into the reactor through a flow meter, and the end is bubbled into the liquid phase through a feed pipe submerged in liquid sulfur.

Agitator may be used to increase the contact efficiency between bubbles and liquids, but it is advantageous to have no agitator in terms of economics and maintenance because high yield can be obtained without a separate agitator.

On the other hand, the bubbling device 23a can be provided in the nozzle part in which carbon monoxide gas is discharged | emitted by liquid velocity (liquid sulfur).

The bubbling device 23a can improve the gas-liquid contact effect and increase the reaction efficiency by dispersing the bubbles of carbon monoxide supplied small.

The bubbling device 23a refers to a bubbler or sparger that generates small bubbles in the liquid to enhance the gas-liquid contact effect, and may be used in any form as long as it can withstand reaction temperature and pressure conditions. have.

However, according to the method of the present invention, carbonyl sulfide can be synthesized in high yield even if no separate bubbling device 23a is provided.

The material of the reactor may be any material as long as it can withstand temperature and pressure, but copper-based metals are susceptible to sulfur and should not be used.

Since carbon steel or iron material is easily oxidized to generate impurities such as rust, it is preferable to use a stainless steel or nickel or nickel alloy metal material.

 The production process of carbonyl sulfide according to the present invention,

Preparing liquid sulfur to melt sulfur in a solid state and remove impurities of sulfur;

A reaction preparation process of maintaining the reaction temperature after transferring the sulfur from which impurities are removed to the reactor;

It consists of a reaction process to carry out the reaction by bubbling carbon monoxide.

Sulfur used in the present invention used solid sulfur in the form of granules or pellets, not in powder form, in order to facilitate the introduction of sulfur as a solid product and to prevent problems such as powder scattering.

After a certain amount of sulfur in a solid state is put into a container prepared in advance and sealed, the solid sulfur is melted by heating with an electric heater installed outside the container while supplying and bubbling an inert gas through a nozzle of an inert gas supply pipe.

When the added sulfur becomes completely liquid, the sulfur is bubbled with an inert gas for at least 1 hour while maintaining the temperature at 125 to 140 ° C. to remove impurities such as moisture.

After the liquid sulfur thus produced is pressurized and transferred to the reactor, carbon monoxide is supplied to the nozzle of the carbon monoxide supply pipe, and the reaction is performed by bubbling the liquid sulfur.

Liquid sulfur is added to the reactor either continuously or batchwise.

Next, the present invention will be described in more detail with reference to Examples.

Example 1

The reactor 21 is a vertical cylindrical reactor made of stainless steel having an internal diameter of 150 mm and a height of 300 mm, and a temperature sensor 25 for measuring internal temperature and a supply pipe 23 having a nozzle formed at an end to which carbon monoxide is supplied.

In order to maintain the temperature outside the reactor 21 by installing an electric heater as a heating means 22 it was possible to control the reaction temperature.

Carbon monoxide was supplied to the reactor 21 through a flow meter, and the experiment was carried out under different conditions by varying the depth of the supply pipe 23 of carbon monoxide.

The reaction temperature in the reactor 21 was maintained at 450 ℃, the reaction pressure was 2kg / cm ² -G.

The reaction product gas flowing out through the discharge pipe 24, the upper pipe of the reactor 21, was periodically collected and analyzed by gas chromatography. The results are shown in Table 1.

Table 1 Reactivity with Nozzle Depth

CO flow rate (l / min) Reaction temperature (℃) Reaction pressure (kg / cm ² -G) Deep Nozzle Depth (cm) COS yield (%) One 450 2 20 98.2 One 450 2 15 82.1 One 450 2 10 25.7 One 450 2 5 4.3

Example 2

The reactor of Example 1 was used under the same conditions as in Example 1 while the reaction temperature (liquid sulfur temperature) was changed to 350 ° C, 400 ° C, 450 ° C, and 500 ° C at atmospheric pressure, respectively.

[Table 2] Reactivity according to reaction temperature

CO flow rate (l / min) Reaction pressure (kg / cm ² -G) Deep Nozzle Depth (cm) Reaction temperature (℃) COS yield (%)  One  Atmospheric pressure  20 350 3.4 400 15.6 450 45.8 500 46.1

Example 3

Using the reactor of Example 1, the reaction pressure was varied while the reaction temperature was maintained at 450 ° C., respectively.

[Table 3] Reactivity according to reaction pressure

CO flow rate (l / min) Reaction temperature (℃) Deep Nozzle Depth (cm) Reaction pressure (kg / cm ² -G) COS yield (%)  One  450  20 0 (atmospheric pressure) 44.3 0.5 53.8 One 75.2 2 98.5 3 97.6

1 is a schematic diagram of a conventional reactor for the synthesis of carbonyl sulfide.

Figure 2 is a schematic cross-sectional view of an apparatus for synthesizing carbonyl sulfide showing an embodiment of the present invention.

[Explanation of symbols on the main parts of the drawings]

21 reactor 22 heating means

23, 27: supply pipe 24: discharge pipe

25: temperature sensor 26: pressure sensor

Claims (9)

In the method for synthesizing carbonyl sulfide (COS) by using carbon monoxide (CO) gas and liquid sulfur (S) as a raw material, The carbon monoxide gas is supplied into the liquid sulfur while bubbling into a reactor capable of controlling the temperature and pressure of the liquid sulfur contained therein so that the carbon monoxide (CO) gas reacts with the liquid sulfur (S) by a gas-liquid contact method. A method for synthesizing carbonyl sulfide. The method of claim 1, A method for synthesizing carbonyl sulfide, characterized in that the reaction is maintained by maintaining the sulfur temperature in the reactor at 350 ~ 550 ℃. The method of claim 1, A method for synthesizing carbonyl sulfide, characterized in that the reaction inside the reactor at atmospheric pressure ~ 5kg / cm ² to react. The method of claim 1, A method of synthesizing carbonyl sulfide, characterized in that the carbon monoxide gas is supplied from the inside of the liquid sulfur. The method of claim 4, wherein A method of synthesizing carbonyl sulfide, wherein carbon monoxide gas is supplied at a depth of 5 cm or more at an interface (water surface) of liquid sulfur. The method according to claim 4 or 5, The carbon monoxide gas is carbonyl sulfide synthesis method characterized in that the supply is bubbling in liquid sulfur. In the reaction apparatus for synthesizing carbonyl sulfide (COS) by reacting carbon monoxide (CO) and sulfur (S), A reactor (21) having an internal space to store liquid sulfur (S), having a heating means (22), capable of temperature control, and pressure control; A carbon monoxide supply pipe 23 installed to supply carbon monoxide (CO) in the sulfur (S) in the liquid phase stored in the inner space of the reactor 21; A sulfur supply pipe 27 installed to supply sulfur (S) to the inner space of the reactor 21; The carbonyl sulfide synthesis reactor, characterized in that configured to include a carbonyl sulfide (COS) discharge pipe (24) for discharging the carbonyl sulfide (COS) synthesized by the reaction installed on the top of the reactor (21). The method of claim 7, wherein Carbon monoxide sulfide synthesis reactor, characterized in that the bubbling device (23a) is installed in the carbon monoxide supply pipe (23). The method of claim 8, The bubbling device (23a) is a carbonyl sulfide synthesis reactor, characterized in that a bubbler or sparger for generating bubbles is used.

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